Chapter 29 - Reaction Types

Question 1

What are the 4 types of reactions? Describe each.

Answer 1

1) Combination Reactions: Two or more reactants form one product
2) Decomposition Reactions: A compound breaking down into two or more substances, usually a result of heating or electrolysis
3) Single-Displacement Reactions (REDOX): When an atom of one compound is replaced by another element

4) Double-Displacement Reactions (Metathesis): Elements from two different compounds displace each other to form two new compounds
- Occurs when one product is removed from the solution as a precipitate or gas OR when two of the original species combine to form a weak electrolyte that remains undissociated in solution
- Neutralization reactions - Occurs when an acid reacts with a base to produce a solution of salt and water

5) Oxidation-Reduction Reactions: A reaction that involved the transfer for elections from one species to another
- Can be divided into two half reactions - oxidation (loss) cause by reducing reagent and reduction (gain) caused by an oxidizing reagent

Question 2

What occurs during a displacement reaction?

Answer 2

Spectator ions do not take place in the overall reaction but remain in solution throughout
- Does not undergo any transformation

Net reaction can be written
- Shows only the participants in the reaction

Question 3

How are oxidation numbers assigned?

Answer 3

1) Free element = 0
2) Monatomic ion = charge of ion
3) Group IA = +1
4) Group IIA = +2
5) Group VIIA = -1
6) Hydrogen = +1
7) Oxygen = -2
8) Sum of oxidation numbers in a neutral compound is 0
9) F = -1
10) Metallic elements = positive oxidation numbers
11) Non-metallic elements = negative or positive